Boat propeller safety cover

ABSTRACT

A boat propeller safety cover includes a soft, flexible, somewhat pouch-shaped body having a stretchable opening sized and structured to receive a propeller unit while the propeller unit is mounted to a recreational water craft. The body may be formed of multiple layers of material, for example, a substantially puncture resistant, or cut resistant material which forms an inner surface of the body and a soft, foam-like material which forms an outer surface of the body. The safety cover provides an effective barrier or buffer between the sharp blades of a propeller unit and a human being, for example, a swimmer, while the boat is docked on the beach, or anchored in open water, for example.

The present invention generally relates to apparatus for boating safety,and more specifically relates to a safety cover for protecting personsand animals from injurious contact with a boat propeller.

Pleasure boating has become an increasingly popular activity. Differenttypes of drive assemblies are available for propelling pleasurewatercraft. For example, drive assemblies including outboard motors aregenerally comprised of a portable frame on which is mounted an internalcombustion engine for power, a drive shaft extending from the engine, apropeller unit having a substantially horizontally orientated propellershaft in communication with a propeller, and a transmission unitpositioned between the drive shaft and the propeller unit to controltransfer of engine power from the drive shaft to the propeller shaft andpropeller.

Outboard motors are typically mounted on a transom of the watercraft insuch a manner that the propeller unit it may be freely pivoted both up,down and side by side, by means of a tiller or handle mounted on anoutboard motor frame opposing the extending drive shaft. In this manner,the tiller may be used to move the extending drive shaft and rotatingpropeller into and out of the water to avoid obstructions and side toside for steering as the boat is propelled.

A popular drive assembly known as an IO drive assembly places thepropeller unit in a position spaced apart from the boat transom and in asubstantially unobstructed position. This can be compared to priorpropulsion systems having a shaft located through a boat hull with thepropeller unit located under the boat and away from the transom.

Boat propellers, like fans, push water to propel the boat. As thepropeller blades rotate, the blade edges virtually cut through thewater, forcing the water over a curved surface of the blade. This actionchannels or redirects the water, imparting the directional thrust neededto propel the boat forward or backward.

It is important to note, in order to gain a clear understanding of oneof the objects of the present invention, that in order to maximize thethrust imparted by a boat propeller, the propeller blades are sharpenedusing machining and polishing techniques effective to produce a nearlyrazor-like edge to these blades.

In nearly all pleasure boating watercraft, the propeller of the driveunit remains at least partially submerged, if not wholly submerged, inthe water when the watercraft is parked on a beach or anchored. It canbe appreciated that this combination of submerged blades havingrazor-like edges, and a recreational setting, presents a serious safetyhazard to swimmers, especially children, who often venture too near asubmerged propeller of an anchored or beached pleasure boat.

For example, for persons entering or exiting a boat while the boat isanchored in open water, egress is commonly made via the transom of theboat or by a “swim step” located directly off of the back of the boatand just above the propeller unit. It can be appreciated then thatunless extreme caution is exercised, a potentially dangerous situationcan result. The proximity of the substantially unobstructed propellerblades located just below the water surface and the primary egresspathway into and out of the boat is a recipe for serious injury. Merecontact with the sharp propeller blade edges can cause injuriesextending from relatively minor epidural lacerations to relatively moreserious deep muscle tissue trauma.

Surprisingly, conventional propeller covers have either not adequatelyaddressed these serious safety concerns or have been primarily orexclusively directed to protection of the propeller unit itself ratherthan protection against human bodily injury resulting from contact withthe unit.

For example, Carlisle, U.S. Pat. No. 5,664,975 discloses a reflectivesafety cover for increasing visibility of a propeller of a motor boatbeing towed by a trailer for preventing rear end accidents.

Miller, U.S. Patent Publication No. 2003/0017763 discloses a fabricsafety enclosure for covering a boat propeller during roadtransportation.

The need for a device for protecting people from injury resulting fromcontact with propeller blades has been recently recognized in Tonokaboniet al., U.S. Patent Publication No. 2005/0066874. Tonokaboni disclosespropeller cover made in the shape of a somewhat, clamshell-like casethat clamps over a propeller unit.

Morton, U.S. Pat. No. 6,152,064 discloses a buoyant enclosure for apropeller that serves as a warning sign to swimmers of the location ofthe propeller. Although Morton mentions that his propeller cover isdesigned to protect swimmers against injury from contact with apropeller, Morton's device is relatively cumbersome to install and useand seems to be more closely directed to a means of alerting swimmersrather than providing an effective barrier between a human being and apropeller blade.

There is a need for more effective, more convenient, easier to use boatpropeller safety cover for protecting people, for example, children,during recreational boating activities. The present invention providessuch a device, with a primary objective being preserving the pleasure ofboating by preventing some of the more common serious injuriesattributable thereto.

SUMMARY OF THE INVENTION

A propeller safety cover apparatus is provided. The apparatus is easy touse, easy to store, and highly effective in preventing injury. Unlikeprior art devices that serve to simply “cover” a boat propeller tothereby make the propeller's position more visible, the presentinvention is designed to provide a cushioning buffer between a humanbeing and sharp propeller blades.

In certain especially advantageous embodiments of the invention, theapparatus of the present invention is structured to provide aneffective, easy to use safety cover for a boat propeller, the apparatusproviding, in use, a soft, impact-absorbent buffer between a human beingand a sharp propeller blade of a boat. Alternatively or additionally,the present invention is structured to substantially prevent such apropeller blade, for example, a newly sharpened propeller blade, frompuncturing or otherwise cutting through the apparatus when the apparatusis in use as a safety cover for a propeller unit.

In accordance with the present invention, a propeller safety coverapparatus generally comprises a body, for example a flexible, pliablebody at least partially made of a soft, cushioning, preferablysubstantially non-water absorbent material, the body being sized to besuitable for covering blades of a propeller unit a boat. The body mayinclude a flexible pouch portion which is sized to enclose orsubstantially entirely contain an entire blade assembly of a propellerunit when such a propeller unit is operationally mounted to a boat. Thebody may further include a resilient, size-adjustable opening structuredto be sufficiently expandable to receive a propeller unit insertedtherein and through the opening, for example, while the propeller unitis coupled to a boat.

In some embodiments of the invention, the pouch potion includes multiplelayers of material. For example, in an exemplary embodiment, the pouchportion includes an inner layer made of a first material that isresistant to being torn, damaged or cut by the propeller blades of whichit is in contact with during use of the apparatus. In this example, thepouch portion further includes an additional layer, for example, anouter layer made of a second material. The second material may bedifferent from the first material in that it is more closely directed toestablishing a buffer, or cushioning barrier between a human being an apropeller blade enclosed in the apparatus during use thereof.

More specifically, the inner layer may be substantially entirely formedof a puncture resistant and/or cut resistant material. For example, thefirst material may comprise a flexible fabric such as Kevlar and/orother suitable material known to be cut resistant and/or puncture proof.In some embodiments of the invention, the inner layer is made of amaterial having a cut resistance effective to substantially prevent apropeller blade, for example, a newly sharpened propeller blade, fromcutting into or through the inner layer.

In addition, the second material which forms the outer layer maycomprise a soft and/or compressible material that forms an outer surfaceof the body of the apparatus. For example, the second material maycomprise a strong, spongy material, for example, but not limited to,Neoprene or other material, for example, Neoprene having a thickness ofat least about 0.1 mm, or about 0.2 mm, or about 0.3 mm, or about 0.5mm, or greater. In one aspect of the invention, the second material is amaterial which has a softness quality that provides a cushioning feel toa human being that comes into physical contact therewith when theapparatus is in use.

Preferably, many of the materials suitable for use in the presentinvention are at least somewhat resistant to deterioration in an aquaticor salt-water environment in order to maintain integrity of the presentinvention for at least one season of use prior to needing replacement.

The outer layer and inner layer may be secured together using anysuitable means. For example, the outer layer and inner layer may be sewntogether along one or more seams thereof. Alternatively or additionally,the outer layer and inner layer may be sealed together along at least aportion of interfacing surfaces between the outer layer and inner layer.Sealing the layers together may be accomplished by, for example, using asuitable adhesive material, or by the application of heat between theinner layer and outer layer during manufacture of the present invention.

In some embodiments of the invention, the opening of the body is definedby a cuff portion structured to be sufficiently enlargeable to enableinsertion of a propeller unit therein, for example, while the propellerunit is mounted to a water vehicle. Preferably, the cuff portion is alsostructured such that the opening, when at rest, assumes a size that issufficiently small to snugly circumscribe a shaft of the propeller unitwhen the apparatus is in use as a safety cover. In a preferredembodiment of the invention, the cuff portion is made of one or moreelastic materials, for example, elastic fabrics. For example, the cuffportion may comprise an elastic fabric and gathered material sewn to, orfolded over and forming an enclosure for the elastic material.

In another advantageous aspect of the invention, the structure of thebody opening does not require the use of ties, zippers, snaps, or otherseparate fastener elements other than the size and resiliency of theelastic cuff portion, to enable insertion and/or removal of theapparatus from the propeller unit.

BRIEF DESCRIPTION OF DRAWINGS

The various aspects and advantages of the present invention may be moreclearly understood and appreciated with respect to the followingDetailed Description when considered in conjunction with theaccompanying Drawings of which:

FIG. 1 is a perspective top view of an apparatus in accordance with theinvention;

FIG. 2 is a partially cut away perspective side view of the apparatusshown in FIG. 1;

FIG. 3 is a perspective view of a boat propeller unit mounted to apleasure water craft that is docked on a beach;

FIG. 4 is a perspective view of the boat propeller shown in FIG. 3,while an apparatus of the invention is being installed thereon; and

FIG. 5 is a perspective view of the boat propeller shown in FIG. 3 withan apparatus of the invention installed over the propeller and beingeffective to protect swimmers against injurious contact with sharp edgesof propeller.

DETAILED DESCRIPTION

Turning now to FIGS. 1 and 2, a propeller cover apparatus 10 inaccordance with an exemplary embodiment of the present invention isshown. The apparatus 10 generally comprises a body 12 having a flexiblepouch portion 14 and a size-adjustable opening 16. The opening 16 isdefined by a cuff portion 18 of the body 12.

More particularly, the pouch portion 14 may be fabricated from one ormore separate, cut out panels of flexible materials sewn or otherwisebound together to achieve the desired pouch-like shape. For example, inthe shown embodiment, the apparatus 10 includes a base region 22 and aside region 24 coupled to the base region 22. For example, the baseregion 22 may comprise a somewhat disc-shaped element 26 having agenerally circular periphery and having a diameter about equal to adiameter of a conventional recreational boat propeller blade assembly(not shown in FIGS. 1 and 2). The side region 24 may comprise a flexiblepanel element 32 including a first edge 34 formed from a seam 38 joiningbase region 22 and side region 24, as shown in FIG. 2. The flexiblepanel element 32 further includes a second edge 42 formed from a seam 42joining the cuff portion 18 with side region 24, as shown in FIG. 1.

It should be appreciated that in other embodiments of the invention notshown, the body 12 may be structured from a unitary piece of materialwith or without seams as shown. For example, it is contemplated that thebody 12 may comprise a flexible, resilient rubber material molded usingconventional means to achieve the desired shape. Alternatively, one orboth of the base region 22 and the side region 24 of apparatus 10 may beindividually formed of multiple panels of material joined together. Allof such variations are considered to fall within the scope of thepresent invention.

In some embodiments of the invention, the apparatus 10 includes multiplelayers of materials, for example, multiple layers of materials havingdifferent compositions, thicknesses and/or other attributes.

For example, in a particularly advantageous aspect of the invention, thepouch portion 14 comprises, at least in part, a cut resistant and/orpuncture resistant material effective to prevent a sharp edge of apropeller blade from slicing through, puncturing, cutting or otherwisedamaging the structural integrity of the apparatus 10 when the apparatusis in use.

In the shown embodiment, the pouch portion 14 of apparatus 10 comprisesan inner layer 50 made of a first material which is a cut resistantmaterial, and an outer layer 54 which comprises a second material thatmay be a material other than a cut resistant material.

As is known to those of skill in the materials art, cut resistance of amaterial may be measured by ASTM and ISO test methods which employforce-distance testers to determine the cut resistance of the materialwhen exposed to a cutting edge under specified loads. An ASTM testmethod (ASTM standard 1790-97) known as the Cut Protection PerformanceTest (CPPT) Method is used to determine cut resistance of a piece offabric. In accordance with this test, a cutting edge is moved across thefabric several times each time under a different load and each time ameasurement of the distance of travel of the cutting edge to cut throughis made. The loads and corresponding distances are graphed to determinethe load (reference load) required to cut through the fabric at 25 mm.The reference load is a measure of cut resistance.

In some embodiments, a light weight Kevlar material or Kevlar blendfabric is employed for the inner layer 50. In other embodiments, amedium weight (14 oz. per square yard) Kevlar material may be used toform the inner layer 50. For example, the material of the inner layer 50may have a cut resistance, under the ASTM CPPT standard, of at leastabout 0.5 kg, more specifically about 0.7 kg, even more specifically,about 0.9 kg, and even more specifically about 10 kg. A heavy weight (20oz. per square yard) Kevlar material has been found to have a cutresistance between 1.3 and 1.4 kg (about 1.3 kg). Kevlar Plus material(also 20 oz. per square yard) has been found to have an even better cutresistance of about 1.6 kg.

Kevlar fiber is a type of fiber of the class of aromatic polyamides oraramids (more specifically, a p-aramid) which is marketed by E.I. DuPontde Nemours and Company of Wilmington, Del. Kevlar Plus material, whichcontains Kevlar fibers, is also marketed by E.I. DuPont de Nemours andCompany of Wilmington, Del. The terms “Kevlar material” and “Kevlarfabric” are meant to include, for the purposes of this specification andthe claims, blends of Kevlar and other fibers which blends have a cutresistance of at least about 0.5 kg, for example, at least about 0.9kg., and including Kevlar Plus material.

Many of these materials and other known cut resistant and/or punctureresistant materials are suitable for forming the inner layer 50 of thebody 12 within the scope of the present invention.

Various combinations of different grades and weights of cut resistantand/or puncture resistant materials, and different weights and/orthicknesses of compressible materials may be used in the manufacture ofvarious embodiments of the invention.

It should also be appreciated that rather than separate layers 50, 54 asshown, the body 12 may comprise, in some instances, no more than asingle, substantially unitary layer of material forming both an outersurface and inner surface of the body 12. In this case, the single layermay be selected to be a material having an effective cut resistanceand/or puncture resistance for preventing propeller blades frompenetrating through the body 12.

Alternatively, rather than the two layers shown, the body 12 maycomprise more than two layers of material, preferably at least one ofwhich is suitably cut resistant and/or puncture resistant. All of thesedifferent variations are considered to within the scope of the presentinvention.

Still referring to FIGS. 1 and 2, in another aspect of the invention,outer layer 54, which generally forms the outer surface of the body 12,may comprise a relatively soft, cushioning material, thereby providing abuffering layer between a human being and the propeller unit enclosedwithin the apparatus 10.

For example, in an exemplary embodiment, the second material which formsthe outer layer 32 is a closed cell, compressible material such as asynthetic rubber. For example, the second material may comprise Neopreneor the like. For example, the material may comprise a Neoprene materialhaving a thickness of at least about 0.1 mm and up to about 5 mm, orgreater. Advantageously, the outer layer 54 may be structured to providea cushioning feel to a human being coming into physical contacttherewith when the apparatus 10 is being used to cover a propeller.

The inner layer 50 and the outer layer 54 may be bonded together by anysuitable means known in the art. For example, the layers 50 and 54 maybe coupled together by adhesives, stitching, heat sealing, or the like.

In yet another aspect of the invention, the cuff portion 18, shown mostclearly in FIG. 1, is structured to be sufficiently enlargeable toenable insertion of a standard-sized propeller unit therein, forexample, while the propeller unit is mounted to a recreationalwatercraft. Preferably, the cuff portion 18 is also structured such thatthe opening, when at rest, assumes a size that is sufficiently small tosnugly circumscribe a shaft of the propeller unit when the apparatus isin use.

For example, the cuff portion 18 may be comprised of one or more bandsof fabric, for example, one or more elastic strips bound together toform a circular opening into to the body 12. The cuff portion 18 may besewn or otherwise fixed to the side region 32 at seam 49. The cuffportion 18 may further comprise a nylon material sewn to the elasticband when the elastic band is in a stretched position. This particularmanner of construction gives the cuff portion 18 a gathered appearancewhen at rest and allows the cuff portion to stretch to enableinstallation of apparatus to a propeller unit. Other arrangements forforming a stretchable, resilient opening of body 12 are alsocontemplated and are considered to be within the scope of the presentinvention. In some embodiments of the invention, the cuff portion 18 issubstantially unitary in construction with the body 12. For example, thecuff portion may comprise the same material which forms the outer layer.

In some embodiments of the invention, at least one of the outer surfaceof the apparatus and the inner surface of the apparatus 10 is structuredto facilitate identification of the correct positioning of the apparatusin use. For example, at least one of the outer surface and inner surfacemay include a distinct color, marking, and/or other indicia that canassist a user in identifying whether apparatus is being correctlypositioned on a propeller unit. For example, the inner surface of theapparatus may be marked with writing, patterning, color, etc. that wouldbe useful to indicate that such surface is the inner, cut resistantsurface which is intended to be positioned directly adjacent thepropeller blades. Similarly, the outer surface of the apparatus may bemarked with writing, patterning, color, etc. to provide indication thatthe surface is the outer, buffering surface of the apparatus. Suchfeatures may be helpful, for example, in the event that the apparatusbecomes inverted or “inside out” after multiple uses, for example.

FIGS. 3-4 illustrate how the apparatus 10 may be used as an easy andhighly effective means to prevent injury to swimmers and other personsduring a recreational boating outing.

Turning now to FIG. 3, a drive unit 60 operationally mounted to awatercraft 66 is shown, the watercraft being parked on a shallow sandybeach. The drive unit 60 includes a propeller unit 68 having sharpblades 70. In FIG. 4, the apparatus 10 of the invention is shown as itis partially installed over the propeller unit 68.

Turning briefly back to FIG. 1, it should be appreciated that theopening 16 formed by cuff region 18 (see FIG. 1) is preferablysufficiently stretchable to enable the opening 16 to be manuallystretched open to a degree that will allow insertion of the propellerblades into the pouch portion 14 without difficulty, for example, by anormal adult human being. The cuff portion 18 is also structured to besized and sufficiently resilient to cause the apparatus 10, when at restover the propeller unit, to snugly fit to a circumference of thepropeller shaft, or at a minimum, at least sufficiently tight to preventthe apparatus 10 from being inadvertently removed or slipped off thepropeller unit.

FIG. 5 shows the apparatus 10 completely installed to the propeller unitwith the sharp propeller blade edges fully covered and no longer exposedto cause injury to swimmers 74.

In another advantageous aspect of the invention, the structure of thebody opening does not require the use of ties, zippers, snaps, or otherseparate fastener elements other than the size and resiliency of theelastic cuff portion, to enable insertion and/or removal of theapparatus from the propeller unit.

It should be appreciated that the present propeller cover apparatus maybe successfully manufactured using materials of construction other thanthe specific materials described herein. In addition, the simpleconstruction of the apparatus enables the manufacture of the apparatusin accordance with the invention, in many different colors, sizes,shapes and designs.

Although there has been hereinabove described one or more exemplaryembodiments of a boat propeller safety cover, in accordance with thepresent invention, for purposes of illustrating the manner in which thepresent invention may be used to advantage, it will be appreciated thatthe present invention is not limited thereto. Accordingly, any and allmodifications, variations and/or equivalent arrangements which may occurto those skilled in the art should be considered to be within the scopeof the present invention as defined in the appended claims.

1. A propeller cover apparatus comprising: a body having a flexiblepouch portion and a size-adjustable opening for receiving a propellerunit; the pouch portion including a first layer made of a firstmaterial, and a second layer made of a second material that is differentfrom the first material.
 2. The apparatus of claim 1 wherein the firstmaterial is at least one of a cut resistant material and a punctureresistant material.
 3. The apparatus of claim 1 wherein the first layerof the pouch portion forms an inner surface of the pouch portion.
 4. Theapparatus of claim 1 wherein the first material comprises a cutresistant fabric.
 5. The apparatus of claim 1 wherein the secondmaterial comprises a substantially compressible material.
 6. Theapparatus of claim 1 wherein the first material is a cut resistantmaterial and the second material is a compressible material.
 7. Theapparatus of claim 1 wherein the second material has a softnessproviding a cushioning feel to a human coming into physical contacttherewith when the apparatus is in use and covering a propeller blade.8. The apparatus of claim 1 wherein the first material comprises a cutresistant material and the second material comprises a compressiblematerial having a softness providing a cushioning feel to a human cominginto physical contact therewith when the apparatus is in use andcovering a propeller blade.
 9. The apparatus of claim 1 wherein thefirst material comprises a Kevlar material.
 10. The apparatus of claim 1wherein the second material comprises a neoprene material.
 11. Theapparatus of claim 1 wherein the first material comprises a Kevlarmaterial, and the second material comprises a neoprene material.
 12. Theapparatus of claim 1 wherein the pouch portion includes base regionhaving a substantially circular periphery and a side region coupled toand substantially circumscribing the base region.
 13. A propeller safetycover apparatus for protecting against injurious contact of a human bodywith a propeller blade comprising: a body comprising a pouch portionincluding a compressible outer surface and a cut resistant innersurface; and a stretchable cuff portion defining an opening into thebody, the cuff portion being structured to be sufficiently enlargeableto enable insertion of a propeller unit into the body while thepropeller unit is mounted to a water vehicle.
 14. The apparatus of claim13 wherein the stretchable cuff portion comprises an elastic material.15. The apparatus of claim 13 wherein the stretchable cuff portion has aresiliency sufficient to cause the apparatus to snugly engage apropeller shaft when the apparatus is in use and covering a propellerblade.
 16. The apparatus of claim 13 wherein the pouch portion comprisesneoprene.
 17. The apparatus of claim 13 wherein the pouch portioncomprises at least two layers of different materials.